A super junction structure may be used in a semiconductor device such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), etc. By using the super junction structure, it is possible to increase the effective doping concentration of the drift layer; and the trade-off relationship between the breakdown voltage and the on-resistance or the trade-off relationship between the breakdown voltage and the on-voltage is improved.
The super junction structure may be provided not only in the element region but also in the terminal region. By providing the super junction structure in the terminal region as well, the electric field spreads into the terminal region easily; and the concentration of the electric field in the element region is suppressed. On the other hand, when the electric field spreads into the terminal region, there is a possibility that the electric field may concentrate in the terminal region; and the breakdown voltage may decrease.